Status of hibernation (suspend to disk) in Guix

[Ivan Vilata i Balaguer <ivan@selidor.net>]

[-- Attachment #1: Type: text/plain, Size: 2114 bytes --]

(I'm not subscribed to the list, please CC me in replies.  Thanks!)

Hi everyone!  As I had promised to myself and some guixers at Capitole du
Libre (salut les collègues !), I finally installed the Guix System in my
laptop (already time after 6+ years of using Guix packages!).  Although my
setup is still in need of some ironing, I was very impressed to see that most
things worked within just a few days of tweaking…  Everyone has done such a
great work! `:)`

In particular, I was very happy to see that hibernation was (nearly) working!
It was sure writing system state to swap then powering off, but then on boot
it routinely ignored the saved state and started a new OS run.  I didn't find
how to fix that in the docs, but by delving into `gnu/build/linux-boot.scm` I
found that I just had to set the kernel argument `resume=<SWAP-SPACE>`, then
resuming worked like a charm. `:)`

In <https://issues.guix.gnu.org/59746> I propose some documentation on how to
set the `resume` kernel argument for hibernation (under the Swap Space
section), so that people is at least able to find some useful indications if
they search for "hibernation" or "suspend to disk".

But then I wonder if I may have rushed to post the patch, as I don't know
whether hibernation is supposed to be more or less mature or supported in Guix
(we may not want to encourage people to use a feature which may easily cause
data loss)…  Though it works quite well for me!

(To be honest, I didn't yet test creating a new system generation with a new
kernel, hibernating, and trying to boot the new kernel.)

Also, since I installed the system manually from a custom `config.scm`, I'm
not sure whether this works out of the box with an installer-made setup, but
my impression was that such an installation on a VM didn't even create a swap
space.  Though installer support may be a whole different discussion. `:P`

So the TL;DR would be: Is it worth adding such documentation, given the
current state of hibernation support in Guix?

Thanks!

-- 
Ivan Vilata i Balaguer -- https://elvil.net/

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]